In kindergarten (n = 361), first grade (n = 321), and second grade (n = 457), a sample of 1139 Swedish-speaking children (587 girls) was examined for reliability and validity evidence regarding the Early Numeracy test (ENtest). Confirmatory factor analysis (CFA), which demonstrated that a four-factor model suited the data much better than a one-factor or two-factor model, produced structural validity proof. Through multigroup CFAs, the known group and cross-cultural validity were established, and it was discovered that the four-factor model equally well fit the gender, age, and language groups. The subskills and test's internal consistency ranged from good to excellent. An appropriate evaluation tool for identifying youngsters who may have difficulty with mathematics learning is the EN-test.